2,719 research outputs found
Single-Photon Switch based on Rydberg Blockade
All-optical switching is a technique in which a gate light pulse changes the
transmission of a target light pulse without the detour via electronic signal
processing. We take this to the quantum regime, where the incoming gate light
pulse contains only one photon on average. The gate pulse is stored as a
Rydberg excitation in an ultracold atomic gas using electromagnetically induced
transparency. Rydberg blockade suppresses the transmission of the subsequent
target pulse. Finally, the stored gate photon can be retrieved. A retrieved
photon heralds successful storage. The corresponding postselected subensemble
shows an extinction of 0.05. The single-photon switch offers many interesting
perspectives ranging from quantum communication to quantum information
processing
Self-Supervised Transformer Model via Hierarchical-Masked-Attention for Medical Image Analysis
Single-Photon Transistor Using a F\"orster Resonance
An all-optical transistor is a device in which a gate light pulse switches
the transmission of a target light pulse with a gain above unity. The gain
quantifies the change of the transmitted target photon number per incoming gate
photon. We study the quantum limit of one incoming gate photon and observe a
gain of 20. The gate pulse is stored as a Rydberg excitation in an ultracold
gas. The transmission of the subsequent target pulse is suppressed by Rydberg
blockade which is enhanced by a F\"orster resonance. The detected target
photons reveal in a single shot with a fidelity above 0.86 whether a Rydberg
excitation was created during the gate pulse. The gain offers the possibility
to distribute the transistor output to the inputs of many transistors, thus
making complex computational tasks possible
Interozeptive Exposition für Subtypen der Panikstörung: Adjustierung der Methode = Verbesserung des Effekts?
In einer multizentrischen randomisierten Studie wurden Wirksamkeit und Wirkmechanismen der interozeptiven Exposition (IE) im Rahmen einer kognitiven Verhaltenstherapie (KVT) untersucht. Insgesamt nahmen N = 154 Patienten mit Panikstörung (16.7%) und Agoraphobie mit Panikstörung (68.9%) teil. Die Behandlung bestand aus 12 Sitzungen und beinhaltete Psychoedukation, IE und Exposition in vivo. Die Wirksamkeit wurde anhand der Veränderung der Schwere der Panikstörung, der Paniksymptomatik, der Angst vor körperlichen Symptomen, der Angst-Sensitivität und der Anzahl spontaner/situativer Panikattacken erfasst.
Untersuchungsschwerpunkt A: Erwartungsgemäß zeigte sich nach Abschluss der KVT eine signifikante Verbesserung aller Outcomes mit kleinen bis mittleren Effektstärken (ES). Die IE führte zur signifikanten Verbesserung der Schwere der Panikstörung, der Angst vor körperlichen Symptomen und der Angst-Sensitivität. Eine Habituation der Angstreaktion ließ sich für alle respiratorischen und für die Mehrzahl der vestibulären Symptomprovokationsübungen nachweisen. Für die Habituation war es unerheblich, wie oft die IE wiederholt wurde. Die Habituation trug lediglich zur Verbesserung der Vorhersage der Angst-Sensitivität nach Abschluss der KVT bei. Es bestand kein Zusammenhang zwischen der Habituation und dem Outcome der IE. Fraglich ist deswegen, ob es sich bei der Habituation über die Sitzungen hinweg um einen bedeutsamen Wirkmechanismus der IE handelt.
Untersuchungsschwerpunkt B: Respiratorische und vestibuläre Subtypen der Panikstörung wurden anhand eines empirischen Vorgehens identifiziert. Die Adjustierung der IE, bei der Subtypen primär mit Symptomen des eigenen Profils konfrontiert wurden, führte bei vestibulären Panikpatienten zu einer signifikant stärkeren initialen Angstreaktion. Eine entsprechend ausgeprägtere Habituation konnte nicht nachgewiesen werden
Bose-Einstein condensate as a quantum memory for a photonic polarization qubit
A scheme based on electromagnetically induced transparency is used to store
light in a Bose-Einstein condensate. In this process, a photonic polarization
qubit is stored in atomic Zeeman states. The performance of the storage process
is characterized and optimized. The average process fidelity is 1.000 +/-
0.004. For long storage times, temporal fluctuations of the magnetic field
reduce this value, yielding a lifetime of the fidelity of 1.1 +/- 0.2 ms. The
write-read efficiency of the pulse energy can reach 0.53 +/- 0.05
How Sustainable is Machine Learning in Energy Applications? – The Sustainable Machine Learning Balance Sheet
Information Systems play a central role in the energy sector for achieving climate targets. With increasing digitization and data availability in the energy sector, data-driven machine learning (ML) approaches emerged, showing high potential. So far, research has focused on optimizing ML approaches’ prediction performance. However, this is a one-sided perspective. ML approaches require large computation times and capacities leading to high energy consumption. With the goal of sustainable energy systems, research on ML approaches should be extended to include the application’s energy consumption. ML solutions must be designed in such a way that the resulting savings in energy (and emissions) are greater than the energy consumption caused using the ML solution. To address this need, we develop the Sustainable Machine Learning Balance Sheet as a framework allowing to holistically evaluate and develop sustainable ML solutions which we validated in a case study and through expert interviews
HIV Activates the Tyrosine Kinase Hck to Secrete ADAM Protease-Containing Extracellular Vesicles
HIV-Nef activates the myeloid cell-typical tyrosine kinase Hck, but its molecular role in the viral life cycle is not entirely understood. We found that HIV plasma extracellular vesicles (HIV pEV) containing/10 proteases and Nef also harbor Hck, and analyzed its role in the context of HIV pEV secretion. Myeloid cells required Hck for the vesicle-associated release of ADAM17. This could be induced by the introduction of Nef and implied that HIV targeted Hck for vesicle-associated ADAM17 secretion from a myeloid compartment. The other contents of HIV-pEV, however, including miRNA and effector protein profiles, as well as the presence of haptoglobin suggested hepatocytes as a possible cellular source. HIV liver tissue analysis supported this assumption, revealing induction of Hck translation, evidence for ADAMprotease activation and HIV infection. Our findings suggest that HIV targets Hck to induce pro-inflammatory vesicles release and identifies hepatocytes as a possible host cell compartment. (c) 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license.Peer reviewe
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